1. Field of the Invention
The invention is directed to a piston-cylinder unit with a cylindrical pressure tube having a surface protection on the outer side of the pressure tube and with a piston axially displaceable in the pressure tube and having a piston rod. The piston rod is guided out of the pressure tube at one end side of the pressure tube through an end side opening through a piston rod guide and sealingly through a piston rod seal. An end region of the pressure tube proceeding from the end side on the piston rod side is excluded from the surface protection, and the end region excluded from the surface protection is coated with a corrosion inhibitor and is covered by a cup-like protective cap configured to surround the end region and having a base at its end on the piston rod side. The base has a coaxial through-orifice through which the piston rod extends in a displaceable manner.
2. Description of the Related Art
In a piston-cylinder unit of the type mentioned above, dirt particles can settle on the portion of the piston rod protruding from the pressure tube and become jammed in the gap between the piston rod and piston rod guide, resulting in damage to the piston rod and piston rod seal. The dirt particles can also adhere to the piston rod seal and directly impair it. In both cases, malfunctions of the piston-cylinder unit can result.